| Tartary buckwheat belongs to Fagopyrum Mill of polygonaceae, which is an unique food medicine dual-use crop in China. Modern medical researches have shown that tartary buckwheat is rich in flavonoids such as rutin and quercetin, which have many pharmacolodical activities such as prevention or treatment of diabetes, hyperlipemia and cancer. In recent years, with the improvement of living standards of people in China, the incidence of chronic disease is growing rapidly. So for, the people suffering from hypertension and hyperlipaemia have been reached 160 million, respectively. The patients with diabetes and obesity are also rapidly increasing every year. Therefore, tartary buckwheat has been paid more attention for its pharmacologic function.This paper researched different kinds of tartary buckwheat (19 varieties in Liangshan, Sichuan) and different parts (seed, bran and leaf), not only determined the profile and content of phenolics and flavonoids but also antioxidant properties using Folin–liocalteu, ABTS·﹢and DPPH·methods, but also deepen the understanding of tartary buckwheat functionality. What's more, the results afford a kind of material which was more stable and better for tartary buckwheat processing. In order to improve the edibility of tartary buckwheat leaves, absorption and utilization of nutritional components and exploited a kind of cake with natural and healthy function. Wheat flour, tartary buckwheat flour and leaf powder were used as raw material, and then the opitimal production technology of tartary buckwheat leaf cake was found by single factor experiment, orthogonal experiments, sensory evaluation and the texture analysis model of TPA. The cake can satisfy the need of sensory quality and nutritional requirements. The results were favourable to further processing and utilization of tartary buckwheat in the future. Furthmore, the results suggested that tartary buckwheat had important application value in the prevention and the treatment of lipid metabolism disorders and scavenging of excess free radicals in human body.The main results of this paper:(1)The phenolic compounds in tartary buckwheat seeds from Liangshan, Sichuan, existed primarily in free forms, which were different from corn and wheat, but, similar to fruit. On average, the phenolic content of tartary buckwheat seeds is 8177.4±4.29μmol GA eq /100g DW,which is 2-30-fold higher than that of fruits , and 5-12-fold higher than that of grains such as corn, rice and wheat. The range of rutin content of 19 tartary buckwheat seeds in Liangshan, Sichuan was 638.91～1263.52mg /100g DW. The content of rutin and antioxidant property was the highest for Jinku-2, so Jinku-2 tartary buckwheat could be suitable for production if the higher antioxidant activity is pursued. Statistical analysis suggested that positive linear correlations were found between rutin contents and DPPH·(R2 = 0.816) or ABTS·+ (R2 =0.763) scavenging ability, respectively. Rutin may play an important part in antioxidant activity among the phenolic compounds. The DPPH·method can be used as rapid qualitative detection in terms of evaluation of rutin content in tartary buckwheat.(2)There were significant differences in total phenolic content among tartary buckwheat leaf powder, bran and whole flour (P<0.05). The phenolic content of leaf powder was highest, followed by bran and whole flour. The total phenolic contents of tartary buckwheat leaf powder were higher than that of other leaf powder, such as lettuce, portulacae, ginkgo and tea leaf powder. The content of bound phenolic in bran was the highest (602.57μmol GA eq /100g DW), Because bound phenolics are associated with cell wall materials that may be difficult to digest, may survive after upper gastrointestinal digestion, and finally reach the colon to exert their health benefits locally, More attention should be paid on the research of bound phenolic of tartary buckwheat in the future.(3)The optimal production technology of tartary buckwheat leaf powder cake was established by the single factor, the orthogonal test, sensory evaluation and Application of TPA Test Mode. The optimal formula was D3A2C1B2, namely, 7% of the leaf powder dosage, 7:3 of the ratio between buckwheat flour and wheat flour, surface fire 200℃/ primer 170℃for baking temperature, 160ml water . Buckwheat cake has a better texture properties and sensory score comparing with the wheat cake.(4)The content of total phenolic in tartary buckwheat cake (462.42μmol GA eq/100g DW) was 1.93 times higher than that in wheat cake. Meanwhile, and was higher than that of peach, banana, pineapple and orange. The contents of total flavonoids in tartary buckwheat cake was 226.232 mg RU eq/100 DW. From the view of total antioxidant ability, tartary buckwheat cake has stronger antioxidant ability than wheat cake by 2.27～2.99 times. |
